Abstract: A hydraulic lifter assembly for adjusting the opening movement of engine valves by push rods actuated by the engine cam shaft is completely self-contained as a unit which may be quickly installed or replaced when necessary. The valve lifter assembly is totally enclosed, so that oil is sealed in the housing and dirt is excluded from the housing reservoir. A plastic indicator cap cooperates with grooves on the exterior of the housing to visually indicate proper valve lifter adjustment and adequate stroke in the operation of the same. The indicator means also makes it apparent when the lifter or adjuster requires attention.